:jens, I suspect that this is due to an outdated version of [ffpuppet](https://github.com/MozillaSecurity/ffpuppet) which grizzly uses as a dependency. Can you pip install from that repository rather than PyPi and try again?
Bug 1740797 Comment 8 Edit History
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:jstutte, I suspect that this is due to an outdated version of [ffpuppet](https://github.com/MozillaSecurity/ffpuppet) which grizzly uses as a dependency. Can you pip install from that repository rather than PyPi and try again?